Hoisting apparatus



May 22, 1928. 1,670,556

v. H. voLLAND HOISTING APPARATUS Filed July 25, 1927 22 24'- ein Passati ay aa, ieaa VICTOR H. ventenni or CLAYTON, ivrrssouiar, Assiettes troveranno SCENIC STU- DIOS, INC., gOF ST. LOUIS, MSSOURI, A, CORPORATION OF M(SSOURI.`

norsrine- APPARATUS.

Application led Julyv 25,

This invention relates to hoisting apparatus and is herein illustrated as embodied in a pulley vor sheave for use in shifting theatrical drops and pieces of sceneiy.

lt is customary to raise and lower stage drops separately by means of several suspension ropes usually attached at` points spaced uniformly along a horizontal lsup'- porting bar disposed within the top edge of each drop. From the supporting bar the ropes are arranged to run upwardly over sheaves or pulleys resting. on a gridiron located directly above the stage, vand thenceto a wall block and aj common counterbalance.

The gridiron, ,which is located high abovethev stage `in which position; it is out of the sight of the audience, is generally composed of numerous bars, or iron beams, extending parallel to each otherand spaced apart- -to permit the passage therethrough of the ropes mentioned above.

The gridirons of various stages are often constructed differently, and even the gridiron of a single stage may be made up of beams of different kinds, vspaced apart unequally, and having dierent shapes. As a vresult ofv this non-uniform arrangement of the gridiron beams, it-'has heretoforev been customary to secure the shea-ves rigidly to the beams and not endeavor to adjust them thereafter. lt will be appreciated `however vthat inasmuch as scenic arrangements are constantly being changed land. re-arranged on ast-age, it would be convenient and highly desirable to provide a sheave that could be adjusted readily, moved from point` to point about the gridiron, and secured ina desired position of adjustment, ynotwithstanding variations in the spacing and shape of the beams to which the sheave is secured.

With the foregoing considerations in mind` the. present invention has for an Cbject thereof the provision of an improved sheave which may, with ease and expediency,

be secured to, and detached from, supports of diiferent shapes, and to supports spaced apa-rt different distances.)

In view of the above designated object, an important feature of the invention resides in providing a sheave with a plurality of clamping means which may be adjusted toward vand away from each other to vary the distance between the clamping means in tween the beams to whichthe sheave is to i927. seriai Nog. 208,123.

`along the extensions, toward and away from the central portion of the'frame, where there is located a rotary pulley wheel. It has been found desirable to providemeans that will insure `against the clamping rii'embersy slip,- ping or otherwise "moving i inadvertently along the extension of the frame, thereby` "disengaging the -sheave from 'the support and rendering .it liable to fall fromffthe'stage gridiron with a probability of injuringisome one on 'the stage beneath7 and consequently,

as illustrated, theuppersurface of thev eX- tensions are provided with notches into means are y'adapted to be seated. "Byvirtu'e ofsuchan arrangement the danger ofthe 'sheave becoming loose and falling from its support is eliminated." f

'Another feature of the inventionconsists in thef provision of a sheave in which the depending 4portion of a rope passingthrough which groove'sformed upon the clamping the sheave will extend through the base of the frame of the sheave at substantially the central portion thereof'. In the illustrated` embodiment of the invention this feature is obtained by making the oppositely-entendi ing projections of the frame i of unequal lengths; the projection kof the frame on the side of the'sheave from which the rope depende being longer than the opposite-projection. `Such a provision insures that the depending rope will always be positioned substantially centrally of the space between the beams upon whichthe sheave is supported, thereby avoiding 'all danger of the depending portion 'of vthe `rope becoming fouledon'thebeama -f Stillv a further feaftureof the invention consists in providing "a sheave lof this character with a guard whichmay be-.removed `with ease' and expediency to permit ready removal of the pulley wheel from theframe, or the quick` insertion of `a new pulley wheel into the frame. j

While 'the invention has been illustrated Y 4and described herein with particular lreferaccord'ance with the width of the space beence toits usev in 'stage work, it is to 'be recognized that the invention may be employed loo i beneficially in any kind of work requiring the use of hoisting apparatus generally.

The above and other features and objects of the invention will become apparent from' a reading "of the following specification in the light of the accompanying drawings, in which: y

Fig. I shows, in perspective, .a viewof my improved sheave.

VFig. II is a view in front elevation of the device disclosed in F ig.` I.

Fig. III is a vertical view, in section, showing the manner in which the pulley wheel is mounted within the sheave.

Fig. IV is a detail view showing the manner in which the sheave may be secured with equal facility to a support entirely different from the. support disclosed in Fig. I.

As shown in the drawings the reference numerals j. indicate vertically extending beams provided with flanges 12, and, as illustrated, these beams are of a type com- -monly employed-in a gridiron of stages to Ain `their lower surfaces.

serve as supports for various hoisting apparatus that is used in shifting scenes and' scenery. 1 i

The illustrated embodiment of my invention is shown in Figs. I, II and III as be- `ing supported upon the beams 10 by means of clamping plates 14, secured to a frame 16 extend between the blocks A26 and the clampuey ing plates 14, and butterfly nuts 32 are pro vided for thc purpose of imparting clamping pressure to the plates 14. f

U As shown in. Figs. I, and II the plates 14,

which rare L-shaped in cross-section, may be adjusted along the smooth, runder-surface of the rame16'until they are in over-lapping engagement with the flangesk 12 of the beams 10. At this time the blocks 26 may be moved into engagement with the notches 24 and the butterily nuts 32 maybetightened, thereby securing the entire sheave in rigid engage ment with the beams upon which it rests. As hereinbelore pointed out, the beams used in the gridirons of different stages, or even the beams used within a single gridiron are oftentimes of different shapes and arranged in a different manner such, for example, as indicated in Fig. IV vof the drawings. As here shown, the beams are arranged with flanges 34projecting downwardly and with flat upper surfaces 36 upon which the projections or `extensions of the frame are adapted to be seated. In securing the sheave to a support of this character, the clamping plates 14 are adjusted away from the smooth under-surface of the'frame 16 until they are so located as to span the flanges 34 of the beams, in which position the butterfly nuts As shown in Fig. II the extensions 20, 22

of the frame 16 are of unequal length, the

extension22 on the side of the'pulley wheel y 18 adjacent to the downwardly extending portion vof the rope 3S being longer vthan the opposite extension 20. The purpose of constructing the extensions in this manner is to avoid all danger of the rope 38 becoming fouled upon the beams 10 of the stage grid. Since the downwardly extending portion of the rope is'off-set from the center of the wheel 18by a distance equal to the radius of the wheel, the extension 22 is, as above stated, made longer than the extension 20 thereby permitting the pulley wheel 18 to be located to the left (as shown in Fig. II) of the center of the space between the beams 10, 10, and the rope 38 to descend substantially near the centerof such space, free and y clear of the supporting beams. j

In the use of devices of this character, it is often desirable to substitute rotary pulley wheels of different diameters or to insert a new wheel when an old one becomes worn or broken. The illustrated sheave is constructed in such a manner that the wheel18 may be quickly .andrk easily removed from the .frame 16 to permit insertion in the frame of a new wheel. Accordingly, and as illustrated, the frame 16 is provided with upwardly extending ears 4O'(Fig.v III)y having openings therein to receive a pin or gudgeon 42 upon which the pulley wheel is adaptedto rotate. A guard 44 is mounted upon the `projecting ears 40 ofthe frame 16, and is provided with depressions 46 for receiving the ears'40. In operation, the pin 42, which as illustrated, is secured in place by means of a Cotter-pin, may be extracted and the guard and pulley be then removed without removing from the sheave the rope 38 which passestherethrough. vA new pulley may be then linserted between the ears 40 of the frame 16, and' rthe guard 44 re-positioned `down over the ears, the depressions 46 Fig. III that the bottom `of the frame 16` is cut away to permit the passage therethrough, and adjustment therealong, of the rope 38, and the clamping bolts 30, respectively. The frame 16 is, however, provided with out- Wardly turned flanges 50 which serve to provide a fiat under-surface on the frame 16.

Having thus described my invention What I claim as new, and desire to secure by Letters Patent of the United States is l. A sheave of the character described lcomprising a frame having a rotary pulleyv Wheel mounted therein, and a plurality of extensions projecting from opposite sides of the frame, said extensions being formed on one side with smooth faces and on the other side with a series of notches for securing in a desired position of adjustment clamping plates arranged to cooperate with the smooth faces of the extensions.

2. A sheave vof the character described comprising, in combination, a pulley Wheel, a frame for supporting the pulley Wheel,

extensions projecting from opposite sides of the frame, a series of notches formed With'- in said extensions, blocks having grooves formed on one of their faces for co-operation a with the notches formed Within the eXtensions, and clamping plates carried by said blocks and arranged for adjustment therewith lengthwise of said extensions.

3. A sheave of' the` character described comprising a rotary pulley Wheel, a. frame for supporting the Wheel, said frame being provided with a plurality of upwardly eX- vieron H. VOLLAND, 

